The present invention relates to novel lubricating compositions.
It has been proposed (U.S. Pat. No. 2,653,910, No. 2,995,569 and No. 3,673,090) to improve the extreme-pressure properties, antioxidant properties and anti-wear properties of lubricating oils by means of additives based on alkyl- or aryl-dithiol-thiones obtained by sulphurization of polyisobutene.
Although among such additives some perform well, they, however, suffer from the disadvantage of being of limited solubility in mineral oils, of having a disagreeable odor and of imparting an intense color to the oil and to the skin. These additives must be handled with care, particularly if they are used in oils employed in metal-working.
It is an object of the present invention to provide a lubricating composition which does not have the shortcomings of the prior art.
It is also an object of the present invention to provide lubricating compositions containing additives and which provide improved properties.
Other objects of the invention will be apparent to those skilled in the art from the present description.